Black Carbon Soot shrank the 19th century glaciers – but why isn’t it listed as a culprit today?

From the University of Colorado at Boulder comes this press release and accompanying photo. The photo, showing hazy pollution laden air in the Bernese Alps, makes me wonder why they don’t attribute current glacier ice loss issues to soot. Asia in particular, is a leader in soot production, right next to those Himalayan glaciers that the IPCC erroneously told us would be gone by 2035.

Mountain peaks in the Bernese Alps protrude above the top of a hazy layer of air. NASA, CIRES and other scientists have uncovered strong evidence that beginning in the 1860s, soot sent into the air by a rapidly industrializing Europe caused the abrupt retreat of mountain glaciers in the European Alps. Credit: Peter Holy

Soot suspect in mid-1800s Alps glacier retreat

Scientists have uncovered strong evidence that soot, or black carbon, sent into the air by a rapidly industrializing Europe, likely caused the abrupt retreat of mountain glaciers in the European Alps.

The research, published Sept. 2 in the Proceedings of the National Academy of Sciences, may help resolve a longstanding scientific debate about why the Alps glaciers retreated beginning in the 1860s, decades before global temperatures started rising again.

Thomas Painter, a snow and ice scientist at NASA’s Jet Propulsion Laboratory in Pasadena, Calif., is lead author of the study, and co-authors include Waleed Abdalati, Director of the Cooperative Institute for Research in Environmental Sciences (CIRES) at the University of Colorado Boulder.

Glacier records in the central European Alps dating back to the 1500s show that between 1860 and 1930, loosely defined as the end of the Little Ice Age in Europe, large valley glaciers in the Alps abruptly retreated by an average of nearly 0.6 mile (1 kilometer). Yet weather in Europe cooled by nearly 1.8 degrees Fahrenheit (1 degree Celsius) during that time. Glaciologists and climatologists have struggled to understand the mismatch between the climate and glacier records.

“Something was missing from the equation,” Painter said.

To investigate, he and his colleagues turned to history. In the decades following the 1850s, Europe was undergoing a powerful economic and atmospheric transformation spurred by industrialization. Residents, transportation, and perhaps most importantly, industry in Western Europe began burning coal in earnest, spewing huge quantities of black carbon and other dark particles into the atmosphere.

When black carbon particles settle on snow, they darken the surface. This melts the snow and exposes the underlying glacier ice to sunlight and relatively warm air earlier in the year, allowing more and faster melt.

To determine how much black carbon was in the atmosphere and the snow when the Alps glaciers began to retreat, the researchers studied ice cores drilled from high up on several European mountain glaciers. By measuring the levels of carbon particles trapped in the ice core layers and taking into consideration modern observations of the distribution of pollutants in the Alps, they could estimate how much black carbon was deposited on glacial surfaces at lower elevations, where levels of black carbon tend to be highest.

The team then ran computer models of glacier behavior, starting with recorded weather conditions and adding the impact of lower-elevation black carbon. By including this impact, the simulated glacier mass loss and timing finally were consistent with the historic record of glacial retreat, despite the cool temperatures of the time.

“This study uncovers some likely human fingerprints on our changing environment,” Abdalati said. “It’s a reminder that the actions we take have far-reaching impacts on the environment in which we live.”

“We must now look closer at other regions on Earth, such as the Himalaya, to study the present-day impacts of black carbon on glaciers,” said Georg Kaser, a study co-author from the University of Innsbruck and lead author of the Working Group I Cryosphere chapter of the Intergovernmental Panel on Climate Change’s upcoming Fifth Assessment Report.

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Other institutions participating in the study include the University of Michigan, Ann Arbor, and the University of California, Davis.

CIRES is a joint institute of the National Oceanic and Atmospheric Administration and CU-Boulder.

I’ve been going on about this for years, but it is the solar insolation – surface albedo interaction that matters with glacier and sea ice melt. Maximum melting occurs after a period of high black carbon and aerosol emissions, when aerosol levels are reduced, as this results in increased solar insolation and reduced albedo as embedded black carbon accumulates on the surface.

Black Carbon Soot shrank the 19th century glaciers – but why isn’t it listed as a culprit today?

Because it’s inconvenient?

Abstract
Dr. James Hansen et. al. – 2003
Soot climate forcing via snow and ice albedos
…..Plausible estimates for the effect of soot on snow and ice albedos (1.5% in the Arctic and 3% in Northern Hemisphere land areas) yield a climate forcing of +0.3 W/m2 in the Northern Hemisphere. The “efficacy” of this forcing is ~2, i.e., for a given forcing it is twice as effective as CO2 in altering global surface air temperature.

It never dawns on them that the thing ‘missing from the equation’ could possibly have been that it became drier as it cooled. Less snow falling in the firn area = glacier retreat.

These people have a mental block except for aerosols and CO2. In the European Alps there is also a lot of Saharan sand deposited on glaciers by southerly winds – it affects both skiing and the summer melt.

“..between 1860 and 1930, loosely defined as the end of the Little Ice Age in Europe, large valley glaciers in the Alps abruptly retreated by an average of nearly 0.6 mile (1 kilometer). Yet weather in Europe cooled by nearly 1.8 degrees Fahrenheit (1 degree Celsius) during that time.”

Not on CET, it didn’t drop 1°C (points 131 to 201), 1865-1872 was a pretty warm period though: http://snag.gy/2q2kT.jpg
and there are known advances during that period, particularly the cold 1880/90’s:

There is a simple way to separate albedo/insolation melt from atmospheric warming melt, which to compare the retreat of nearby south facing to north facing glaciers. This can be done either with glaciers on volcanos, which are conveniently symetrical, with 12 to 14 glaciers going in all directions, or with east-west mountain chains like the Himalayas.

I have inferred this ratio from several studies and estimate that insolation/albedo melt could be anywhere between somewhat less than 50% (Mount Rainier) to greater than 100% (in the Himalayas).

That such a study has never been done, speaks volumes about how climate science research is carefully managed to avoid inconvenient results.

If Mann’s hockeystick reconstruction of the Little Ice Age temperatures is correct, the small drop in global temperature during the LIA was not enough to cause the glaciers to advance. Furthermore the rapid retreat of glaciers in the European Alps began in the 1800’s before global temperatures had sufficiently risen. Several researchers call this the Little Ice Age paradox.
Read Vincent C, et al., (2005) Solving the paradox of the end of the Little Ice Age in the Alps. Geophysical Research Letters, vol. 32, L09706, doi:10.1029/2005GL022552

I would have bet that much of the glacial retreat was due to a dry period similar to why Kilimanjaro glaciers are shrinking, but black soot is a believable explanation. Either way, retreating glaciers often have nothing to do with the global temperature. The real mystery is why they keep blaming CO2.

@MIke McMillan Doesn’t glacial advance and retreat have something to do with snowfall in the source region?

Absolutely. While the western Himalayan glaciers in the Karakoram added mass, the eastern Himalayan glaciers declined. Easter Himalayan glaciers depend on moisture from the summer monsoons, and during the warm phase of the Pacific Decadal Oscillation, the more frequent El Ninos divert moisture away from the Himalaya and thus less snowfall.

Likewise the North Atlantic Oscillation diverts moisture and snow northward during the positive phase causing the Norwegian glaciers to increase while the glaciers in the Alps are starved for precipitation and shrink. Kaser is one of the authors of the black soot study and wrote about the European glaciers, “Only Europe showed a mean value close to zero, reflecting the strong mass losses in the Alps being compensated by mass gains in maritime Scandinavia until the end of the 20th century”

Kaser also exposed the fact that Kilimanjaro was shrinking due to less moisture eventhough tempeatures always remained below freezing, writing “The near extinction of the plateau ice in modern times is controlled by the absence of sustained regional wet periods rather than changes in local air temperature on the peak of Kilimanjaro”. read Kaser, G., et al. (2012) Is the decline of ice on Kilimanjaro unprecedented in the Holocene?. The Holocene, OnlineFirst, published on July 19, 2010 as doi:10.1177/0959683610369498

And why not soot for the rapid melting of the Arctic ice cap? The new Chinese coal plants are very likely the cause there. It would also explain the difference between the Arctic and Antarctic ice cap loss, especially the sudden loss since the mid 1990s.

There could be some truth in this, but 5.500 years ago, a large volcanic dust eruption, ignited a glacier melt and they found Outzi the iceman. But it was temporary. The dust for some reason enabled the glazier to melt in the Alps between Austria and Italy.

This study tends to support those of us who advocate efforts to reduce particulate pollution. The negative impact of particulate pollution on human health has already been established beyond any reasonable doubt. This study suggests that further reductions could lead to some restoration of our glaciers too.

If and when this study receives any attention in the mainstream media, I fear the distinction between “black carbon” and “carbon dioxide” will be comprehensively blurred. In other words, it will be played out as further justification for the silly war on CO2.

In reality, we can make significant improvements to the condition of our planet with modest investments by reducing particulate pollution from man-made sources. Sadly, this doesn’t fit the current political agenda and such sensible alternatives will be summarily ignored.

Part of me wonders just how much the change really is. Anyone see the streets of Chicago from October to April? The piles of snow are brown and black as all get out and become mounds of ice. I can’t imagine anything which should retain heat as much as gravel laden ice.

Only unburnt soot is (presumably) black, the burnt ash component is white.

I am suspicious of the soot story, the precipitation and oceanic oscillation explanation seems much stronger. The only human fingerprint is the relentless eco-revvisionism seeking to deny any cause of climate change other than human input to the atmosphere.

Corky Boyd says:
September 4, 2013 at 8:19 pm
And why not soot for the rapid melting of the Arctic ice cap? The new Chinese coal plants are very likely the cause there.

The cause is the shutdown of Soviet era industries, diesel engines and a few other sources on the Kola Peninsula. Which resulted in reduced Arctic black carbon and aerosols, and hence aerosol seeded clouds. So more solar insolation on sea ice with high levels of embedded black carbon.

There are 3 locations where BC and aerosols (from memory SO2) are measured in the Arctic, Svalbaard, a place in the Canadian Arctic, and Barrow. All 3 show reduced black carbon, and the first two reduced aerosols. Only Barrow showed no significant change in aerosols, likely due to China emissions.

“The research, published Sept. 2 in the Proceedings of the National Academy of Sciences, may help resolve a longstanding scientific debate about why the Alps glaciers retreated beginning in the 1860s, decades before global temperatures started rising again.”

That statement isn’t true. Rather, global temperatures were rising long before decades after the 1860s (unless they have an extra-fudged, extra-revisionist temperature source being used, in which case it is untrue by contrast to other data sources including those published prior to the political era). Global temperatures rose since the Little Ice Age.

For instance, a plot within the following shows Andes (South American) glacial retreat throughout the 19th century (aside from a temporary advance near its start when there was the Dalton minimum in solar activity) and how such matches to the pattern in cosmic ray forcing:

Any effect from soot would be on top of how there would naturally be glacial retreat in the 19th century and beyond (after the LIA ended) anyway.

“Yet weather in Europe cooled by nearly 1.8 degrees Fahrenheit (1 degree Celsius) during that time [1860 to 1930].”

What these activists think they can get away with now is amazing; unfortunately they are probably not much underestimating how many people will fall for their claims without the slightest bit of cross-checking.

The effect of soot on Arctic glaciers was noted by Scoresby on his first Arctic expedition in the 1820’s. Ahlman listed the causes of the declining glaciers of Europe, Alaska and New Zealand from the 1850’s in various comprehensive scientific reports from the 1930’s as did Gordon Manley-who constructed CET.. From this we know that temperatures have been generally rising since the coldest decade of the LIA in 1690

Every generation we seem to need to rediscover things about the climate that observations had already taught us.
tonyb

I detest the term “black carbon.” To me, it is simply old-fashioned soot. The “black carbon” label was invented to contrast with the current mania demonizing invisible carbon dioxide. It serves the purpose of propaganda and environmental correctness – not clarity of expression or clear thinking.

Ummmm, no. Soot is caused by an incomplete burning process of any fuel. Forest fires, for example emit huge amounts of soot. Those in poorer countries, without access to grid-supplied electricity will burn dung and whatever else is available, often in open fires, emmitting lots of soot.
Modern power plants are highly efficient, and do not emit soot. The same with modern vehicles.

This whole soot thing is a red herring in any case. It’s an back-door attempt to tie CO2 and soot together, since we know soot is bad, but for completely different reasons. Soot is unhealthy to breathe, and especially affects those forced to rely on inefficient, dirty methods of supplying energy.

“Glacier records in the central European Alps dating back to the 1500s show that between 1860 and 1930, loosely defined as the end of the Little Ice Age in Europe, large valley glaciers in the Alps abruptly retreated by an average of nearly 0.6 mile (1 kilometer). Yet weather in Europe cooled by nearly 1.8 degrees Fahrenheit (1 degree Celsius) during that time.”

I noted how such is untrue in my prior post since Europe, the Northern Hemisphere, and the world warmed rather than cooled over the 1860 to 1930 period.

However, as I wrote it quickly, I skipped adding in an illustration specifically for the Alps subpart of Europe.

If anyone wondered if they had the opposite temperature trend of their surroundings, the opposite of Europe in general: They didn’t, and here is a further illustration:

As the above notes, in fact, with further continuing temperature rise after 1930, there was “the warmest (1940s)” years.

The paper I linked above looks like data not fudged for CAGW convenience, so it shows the truth of 1940s temperatures being warmer than more recently up through its endpoint of 2003. It also mentions the prime influence of solar forcing, remarking and showing how “warm summers seem to coincide with periods of high solar activity, and cold summers vice versa.” (That is a subpart of the general picture in my http://s24.postimg.org/rbbws9o85/overview.gif ).

I’m not saying soot has no effect (though there is not huge room for such in context), but the soot article is just another example of how those trying to argue manmade influences dominated for yet another part of climate tend to be activists, in turn often having the same level of honesty (dishonesty) prevalent among other CAGW activists.

A non-activist would observe the correlation with solar/GCR activity, like that in the prior links, and, if looking into manmade soot, see if any little bits of the prior big picture could be further refined by such, while being honest enough to not mind substantially mentioning the former too, rather than not even mentioning solar variation in the 2-page press release.

(My guess for why Anthony Watts’s default first reaction was relatively liking the soot paper is perhaps because of thinking soot should be more looked at now rather than the emphasis primarily just on CO2 for modern arctic ice variation; while there is some merit to that, really there isn’t much, if practically any, arctic ice variation even in recent years beyond what natural causes can explain, as http://s24.postimg.org/rbbws9o85/overview.gif indirectly suggests, once sidestepping cherry-picked moments and rather looking at trends in the annual average).

(My guess for why Anthony Watts’s default first reaction was relatively liking the soot paper is perhaps because of thinking soot should be more looked at now rather than the emphasis primarily just on CO2 for modern arctic ice variation; while there is some merit to that, really there isn’t much, if practically any, arctic ice variation even in recent years beyond what natural causes can explain, as http://s24.postimg.org/rbbws9o85/overview.gif indirectly suggests, once sidestepping cherry-picked moments and rather looking at trends in the annual average).

I write to seek clarification, please.

As I read that, I understand you to be suggesting that CO2 is “primarily” responsible for “modern arctic ice variation”.

Have I misunderstood you and, if so, what did you intend to say?
Or
Have I understood you and, if so, were you joking?

For example, roughly around 5/6ths of the way down in it, you can see what I think of CO2 compared to arctic climate history: the Soon 2005 plots, showing what has terrible lack of correlation (CO2) versus what fits.